A sheriff's deputy at the scene said at least two of the crashes resulted in lower back injuries. None of the injuries appeared critical.

Hauser Dunes Rescue took at least two people off the sand.

Dune riding is a classic Coos County summer pasttime, but accidents like Friday's argue for safety.

"They always need to make sure their flag is flying high," said Lisa Kessler with the Oregon Dunes.

"Don't fly over dunes," cautioned Keely Hackett at Steve's ATV Rental. "That's bad because they could drop off. Turn to the right or left, kind of see what the hill looks like, then go down."

"Always wear your helmet," advised ATV mechanic Cody Anderson. "Riding gear is best. When you come up a dune, you want to slow down. When you go down the other side, you want to make sure there's not a big drop off."

"Look out for other people," he added. "You don't want to hit anybody."

Follow that advice, and you should have a safe - and fun - day at the dunes.